CSS Solved Everyday Science (GSA) Past Paper 1987

CSS Solved Everyday Science (GSA) Past Paper 1987

The CSS Solved Everyday Science (GSA) Past Paper 1987 is written by one of the best CSS GSA teachers Miss Ambar Fiaz. She has solved many CSS GSA past papers and has provided guidance to thousands of GSA students how to score up to 90 and how to attempt the GSA paper. On the special request of CSSPrepForum, Miss Ambar Fiaz has solved another CSS EDS (GSA) past paper. Nowadays, GSA paper contains 20 MCQs. To score 20 marks, try covering all of the MCQs available at Howfiv website (EDS MCQs & GSA Past Papers) because 17 to 18 MCQs are asked straight from the website for years.

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CSS Solved Everyday Science (GSA) Past Paper 1985
CSS Solved Everyday Science (GSA) Past Paper 1986
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Question – 01:

What are the achievements of the following scientists?
Muhammad bin Zakaria, Ibne-al-Hasham, Jabir bin Hayyan, Ibne Rushd, Mendal, Watson and Crick, and Lamarck. 


1) Muhammad bin Zakaria:

He was an Iranian scholar, researcher, physician, and alchemist. 


His peerless achievement was he divided the chemical compounds into four main groups given below:
·   Mineral
·   Vegetable
·   Animal
·   Derivative

2) Ibne-al-Hasham:

He was asserted “the father of modern optics”.


In the 11th century, he described the structure and function of the eye. He made a notable contribution in the field of optics. He also wrote a book “Book of Optics”, which is available in Latin edition.

3) Jabir bin Hayyan:

He was known as “the father of Arab Chemistry”.


He was one of the founders of modern pharmacy. He is famous for introducing the method of preparation of Nitric acid and Hydrochloric acid. He also did exceptional work in steelmaking, dyeing of cloth and leather, and varnish making.

4) Ibn Rushd:

He was a well-known scholar of Natural Sciences.


He did remarkable work in the field of medicine. He was the discoverer of free-thinking movement. He wrote more than 100 books on various topics. He also served as a chief judge for so many years.

5)  Mendal:

He was a scientist and teacher by profession.


He was the pioneer of the principle of heredity and set the mathematical foundation of the science of genetics. His written work includes experiments on plant hybridization. His work got published in 1866, which demonstrate genes to determine the traits of an organism. He also introduced two fundamental laws:

i.     Law of segregation
ii.     Law of independent assortment

6) Watson and Crick:

 Watson and crick were scientists who were working together.


They worked together and in the 1950s it was the discovery of DNA that made them famous. DNA contains the hereditary material of the cells.

7) Lamarck:

He was a French biologist by profession.


Lamarck introduced the theory of evolution. According to the theory, the physical change is an organism; such as the development of an organ, can be transmitted to their offsprings. He also contributed to science as a botanical and zoological systematist.

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Question – 02:

Who discovered or invented the following. Answer any five?
Penicillin, X-Ray, Telephone, Circulation of blood, Bicycle, Dynamite, and Mercury Thermometer


The invented items with respective pioneer are tabulated below.

Alexander FlemingPenicillin
Wilhelm RoentgenX-Ray
Alexander Graham BellTelephone
William HarveyCirculation of blood
Karl von DraisBicycle
Alfred NobelDynamite
Daniel Gabriel FahrenheitMercury Thermometer
by Miss Ambar
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Question – 03:

(a) What do you understand by blood pressure?
(b) What is the blood pressure in man under normal condition?
(c) What is Reflexive Action?
(d) What is the difference between a virus and a bacterium?
(e) Name any viral disease special to children.


(a)Blood Pressure:

It is the amount of force exerted by the blood on the walls of arteries. Blood pressure measures that how much amount of the force is being applied on the walls of arteries.

How it is measured?

It is measured in millimeters. It consists of two types of pressure:

·   Systolic pressure:
When the heartbeats, the amount of force by blood against arteries can be measured is known as systolic pressure.

·   Diastolic pressure:
It is the measurement of blood pressure during the period when the heart is at rest position between heartbeats. It is defined as diastolic pressure.  

Source Google

This is how blood pressure is measured. It is measured by the digital instrument called sphygmomanometer as shown in the figure below.

(b) Blood Pressure in man under normal condition:

The blood pressure in man under normal condition is from 80mmHg (diastolic) to 120mmHg (systolic), but it may vary from person to person according to their age and physical health. The ideal amount of blood pressure in normal condition is 120/80 mmHg as shown in the figure.

Source Google
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(c) Reflexive Action:

An involuntary or unconscious movement of an organism in the result of stimulus is known as a reflexive action. The stimulus can be anything that can precipitate a change in behaviour or motion of the body.


If a barefooted person is walking in a room, and unconsciously his foot touches a nail, present on the floor. He will immediately pull back his foot in an upward direction to save himself from getting injured. It is called a reflexive action.

Why it happens?

It happens because of sense organs present in the body. They immediately convey the message to the brain and it allows the body to react accordingly.

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(d) Difference between Virus and Bacterium:

The difference between virus and bacterium is tabulated below:

It is living organism.It is non-living organism.
It is made up of cells.It is not made up of cells.
It is larger in size. (1000nm)It is smaller in size. (20-400nm)
It may cause dangerous diseases; such as, tetanus, TB, pneumonia, food poisoning, and cholera, etc.It may cause diseases like measles, mumps, flu, cold sores, and aids, etc.
It can be treated by antibiotics.Antibiotics don’t work in this case. Antivirals are used to cure the disease. 
It can reproduce independently by cell division.It always needs a host cell for reproduction.
by Miss Ambar

(e) Viral diseases in children:

Some of the viral diseases in the children are given below:

  1. Chickenpox
  2. Influenza (Flu)
  3. Mumps
  4. Measles
  5. Shingles
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Question – 04:

(a) What do you understand by immunity?
(b) What is the principal of immunization?
(c) Why is matching of blood groups done before giving blood transfusion?
(d) What is the principal of pasteurization?


A) What do you understand by immunity?

The ability to fight against a particular infection or disease and preventing the production of pathogenic microorganism- that causes disease- in the body is called Immunity. Immunity is of two types:

  1. Active Immunity
  2. Passive Immunity

A strong immunity system keeps body healthy and active as they are more capable to fight against the infections or diseases.

B) What is the principal of immunization?


It is a process by which vaccine is given to a person for fighting against the disease. It is done by various techniques but vaccination is the most commonly used method of immunization. It makes the body capable to fight against infection or disease. Immunity can also be acquired by inoculation or injection. The body can also be cured by the process of Active and Passive immunity explained hereunder.

1- Active Immunity:

When a person gets infected by a disease, the immune system itself creates antibodies to protect the body from pathogens is called Active immunity.

2- Passive Immunity:

In passive immunity system, antibodies are produced by an external source or a host and then transferred to the body. For example, a mother introduces antibodies, which are transferred by the mother’s milk to the children. This is how passive immunity works.

These are few methods of immunization.

C) Why is matching of blood groups done before giving blood transfusion?

When it comes to blood transfusion, acquiring the same blood group is essential. If the blood group of the donor is incompatible to the receiver, it may cause serious issues in the receiver’s body. It causes clumping of the antibodies to the red blood cells, which is called agglutination, in the patient’s body that can be lethal. The process of agglutination in which red blood cells are coated with antibodies is shown in the figure below:   

Source Google

This is why matching blood groups are essential before giving blood transfusion.

D) What is principal of pasteurization?

In order to extend the shelf life of food and beverages, heat is applied to kill the pathogens is called pasteurization. It inactivates the microorganisms that are harmful and reduces the shelf life of the food. The heat, which is applied, is below 100°C. By this method, only harmful microorganisms can be killed, but it is unable to destroy the bacterial spores. This is the reason that it cannot be used to sterilize the products. It only inactivates the enzymes that spoil the food. It can be used for both solids and liquids. The products, which are commonly pasteurized, are given hereunder.

  • Dairy products
  • Eggs
  • Fruit juices
  • Milk
  • Nuts
  • Syrup
  • Vinegar, etc.
Source Google

The method of pasteurization of milk is shown above in the figure. The pasteurized products also retain their original taste and freshness. This is the principal of pasteurization.

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Question – 05:  

Name the diseases which are caused by the deficiency of the following?
Vitamin A, Vitamin B1, Vitamin C, Vitamin K, Insulin, Iodine, Gastrin.


The effects of the deficiency of the following nutrients in the human body are given as follows:

Vitamin A:

The deficiency of vitamin A in the human body causes:

  • Inflamed skin.
  • Night blindness
  • Infertility
  • Delayed growth
  • Respiratory infections
Vitamin B1:

The deficiency of vitamin B1 in the human body causes:

  • Beriberi disease
  • Weight loss
  • Mental problems
  • Short-term memory loss
Vitamin C:

The deficiency of vitamin C in the human body causes:

  • Fatigue
  • Inflammation of the gums
  • Small red or purple spots on the skin
  • Joint pain
  • Corkscrew hair
Vitamin K:

The deficiency of vitamin K in the human body causes:

  • Easy bruising
  • Oozing from nose and gums
  • Bleeding from wounds

The deficiency of insulin in the human body causes:

  • Diminished protein synthesis
  • Poor weight gain
  • Reduce ability to overcome infections

The deficiency of iodine in the human body causes:

  • Hinders mental and physical growth
  • Body dries up
  • Skin thickens
  • Face gets wrinkle
  • Enlarge thyroid glands

The deficiency of gastrin in the human body causes:

  • Increases the risk of infection in the digestive system
  • Limits the stomach’s ability to absorb nutrients

These are the effects of the deficiency of the following nutrients in the human body.

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Question – 06:

Fill in the blanks.

Question – 06: Fill in the blanks.

  1. A process of digestion begins in Mouth.
  2. Sometimes when white blood corpuscles greatly increase in number, they cause a disease called Leukemia.
  3. The principle of wireless telegraphy was discovered by Signor Marconi.
  4. Earth is one of Nine planets which revolved around the sun.
  5. The planet nearest to the sun is Mercury.
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Question – 07:

Write notes on any five of the following.

  1. Nuclear fission
  2. Cast Iron
  3. Bronze
  4. German silver
  5. Washing Soda
  6. Caustic Soda
  7. Nebula


1- Nuclear Fission:

The process in which one heavy nucleus is breakdown into two small nuclei is called nuclear fission reaction, and the amount of energy obtained by this process is called nuclear fission energy.

Source Google

In a nuclear fission reaction, the nucleus of the Uranium is used for bombardment. The nucleus is bombarded with a neutron, which breakdown the nucleus into two smaller nuclei. The amount of energy, 200MeV, is released in each fission reaction. Most of the energy released in the process is converted into heat, which is later used in a nuclear power plant to generate steam. When Uranium-235 is bombarded with a neutron, it is broken down into Barium and Krypton and two more neutrons with the release in energy.

Chemical Equation:          

Chemical equation of nuclear fission reaction is given below:

92U235+ 1n1 56Ba144+36Kr90+2n1+ Energy

This is how nuclear fission reaction is sustained.

2- Cast Iron:

It is comprised of iron-carbon alloys in which carbon content is more than 2%. Varying amounts of silicon, manganese, and traces of impurities; such as sulfur and phosphorus are also used in its formation. Its usefulness derives from its relatively low melting temperature. It is widely used in the kitchen utensils used for pan-frying, roasting, baking, and broiling, etc. It distributes heat very beautifully in the pot, which makes the cooking experience even more even. It remains hot for a few minutes even if you turn off the flame.

Source Google

Along with advantages it also has few disadvantages given below.

  • It is vulnerable to rusting.
  • It has poor machinability as compare to steel.
  • It has poor resistance.
3- Bronze:

It is made up of copper and tin. It was formed before 3000BC. In its composition, 5-20% tin is added to make it stronger. It is widely used in so many applications; such as springs, bushings, bearings, and similar fittings. It is also used in guitar and piano strings.  Bronze is a little bit expensive than others because of its way of manufacturing.

Source Google
4- German silver:

Contrary to its name, it is not made up of silver. It is called German silver because of its resemblance to the texture of the silver. It is made up of copper, zinc, and nickel. The amount of copper, zinc, and nickel used is 60%, 20%, and 20% respectively. Because of its toughness, hardness, and resistance, it is widely used in tableware, marine fittings, heating coils, and plumbing fixtures. It is also used in less expensive jewellery for plating. Along with benefits, it may also cause rashes, itching, dry patches, and redness to the skin because of zinc and nickel, present in it. It should be washed in warm water.

Source Google
5- Washing Soda:

It is a chemical compound, transparent crystalline solid, made up of sodium, carbon, and oxygen. Its chemical formula is Na2CO3. It is used to remove stains from clothes. It is present in both liquid and powder form. It is widely used at homes in laundry and kitchen.

Source Google
Chemical composition:

It is comprised of two sodium, three oxygen, and one carbon molecule. Chemical composition of washing soda is shown below.

6- Caustic Soda:

It is an inorganic compound made up of sodium, hydrogen, and oxygen. Its chemical formula is NaOH. It is used to manufacture paper, alumina, soap, detergents, and petroleum products.  It is also used in applications; such as water treatment, food, textiles, metal processing, mining, and glass making, etc. To use this, some precautionary measures are required. One should wear rubber gloves and eye protection as it may lead to severe eye damage.

Source Google
7- Nebula:

In space, a cloud of dust and gas is called a nebula. Nebulae are made up of dust, hydrogen, and ionized gases. They are formed either by the explosion of a dying star or are regions for the formation of new stars. It acts as a nursery for new stars. It is a very thin material and considered a good vacuum on the earth. They appear solid and bright in colours. In a dark night, it is visible to the unaided eye. About 3000 planetary nebulae are present in our galaxy.  They are present in many shapes; such as, bipolar, spherical, and elliptical, etc. An image of nebulae is shown below.

Source Google
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Question – 08:

(a) What is the function of root tubers?
(b) What is the main difference between an animal and a plant cell?
(c) Why are the leaves of pine tree needle-shaped?
(d) How is the age of the tree is determined?

(a) What is the function of root tubers?

The function of root tubers:

In plants, tubers are used to store the nutrients, which can be used later for the survival of the plant in winter or dry months. They are usually short and grow under the soil. It also stores energy in the form of starch, which helps in the growth of the new stem. It provides food to the new plant until it becomes able to produce by owns self. Examples of few plants having tuber are potatoes, Jerusalem, jicama, and yams, etc. The figure below describes how a tuber looks like.

Source Google
(b) What is the main difference between an animal and a plant cell?

Difference between an animal and plant cell:

The difference between an animal and plant cell is given below:

Plant CellAnimal Cell
The cell wall is present.No cell wall is present.
It has plasmodesmata.It does not have plasmodesmata.
It has one large vacuole.It has many small vacuoles.
Nucleus is present on one side of the cell.Nucleus is present in center of the cell.
It is larger in size having regular shape.It is smaller in size having irregular or round shape.
A well labeled diagram of the plant cell is shown hereunder. A well labeled diagram of the animal cell is shown hereunder.  
by Miss Ambar

These are the basic differences between an animal and a plant cell.

(c) Why are the leaves of pine tree needle-shaped?

Pine trees are usually found in cold areas. In needle-like leaves, the stomata are tightly packed, which not only helps to retain the moisture but also prevents the water loss from the leaves. The needle-shaped leaves are able to capture the sunlight for an entire year. Needles prevent the tree to fall over during a big storm. They are more capable to survive ice and snow as compared to flat leaves. This is why the leaves of a pine tree are needle-shaped. The needle-shaped leaves of a pine tree are shown in the figure given below.

Source Google

(d) How is the age of the tree is determined?

To determine the age of tree:

The age of the tree is determined by counting the annual rings formed in the stem of the tree as shown in the figure below.

Source wikiHow
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Question – 09:

(a) Describe the process of photosynthesis in plants?
(b) Name the positively phototropic and negatively phototropic parts of plants


Photosynthesis in plants:

The process by which plants make their food is called photosynthesis. In this process, light energy is converted into chemical energy. Plants absorb the light from the sun and use it to convert carbon dioxide (CO2), water (H2O), and minerals into glucose (C6H12O6) and oxygen. Glucose is the food, which is required by the plants for their growth. In photosynthesis, gases (carbon dioxide and oxygen) are exchanged with the help of stomata, present on the leaves.

Source Google

In this process, six molecules of carbon dioxide react with six molecules of water in the presence of light, absorbed by chlorophyll, are converted into a glucose molecule and six oxygen molecules. The chemical equation of photosynthesis is given below.

Chemical Equation:

6CO2 + 6H2O → C6H12O6 + 6O2.

This is the chemical equation of photosynthesis.


When the plant shows growth in response to light, is called phototropism.

Source Google

Positively phototropic parts of plants:

The positively phototropic part of the plant is stem. It shows movement when light falls on it.

Negatively phototropic parts of plants:

The negatively phototropic part of the plant is root. It shows movement due to geotropism, not phototropism.

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Question – 10:

(a) How a rainbow produced?
(b) What are the component colours of the rainbow?
(c) What do you know about the Milky Way?
(d) Why do you hear thunder after, and see a flash of light first?
(e) How an earthquake caused?


(a) How a rainbow produced?

After the rain, few droplets remain in the sky. When sunlight falls on the raindrops, some of the light reflects back, while the rest of the light refracts back. White light falling on the droplets splits into different colours. By this, light reflects behind the raindrops and more refraction occurs. It causes the formation of colours with more dispersion. It always forms in opposite direction to the sun. In a rainbow, red colour is more visible than others. This is how the rainbow is formed.

Source Google
(b) What are the component colours of the rainbow?

The spectrum of light in rainbow includes following colors:

  • Red
  • Orange
  • Yellow
  • Green
  • Blue
  • Indigo
  • Violet
(c) What do you know about the Milky Way?

The galaxy of our solar system is Milky Way. It is called Milky Way because it appears as a milky band in dark night. It contains 90% of dark matter and 10% luminous matter. According to the estimation of Astronomers, it is made up of approximately 100 billion stars. Except this, there are millions of other galaxies in the universe. According to scientists, in Milky Way galaxy, there may be tens of billions of solar systems in it. It is not still, but moving constantly. The solar system travels at an average speed of 515,000 mph (828,000 km/h).

Source Google
(d) Why do you hear thunder after, and see a flash of light first?

If we see the sky, we always see the lightning before after we hear the thunder. That is because light travels much faster than sound waves. It takes approximately 5 seconds for the sound to travel 1 mile. Thus, It happens because light travels much faster than sound.

Speed of sound= 343 m/s

Speed of light = 299 792 458 m / s

Source Google
(e) How an earthquake caused?

Inside the earth’s crust (outer layer of the planet, earth), released built-up pressure causes an earthquake. When the rocks present underground shakes or breaks suddenly by an incident, it also causes an earthquake. Its effects include ground shaking, ground rupture, landslides, and liquefaction. It mostly occurs along the edge of oceanic and continental plates. 90% of the earthquakes occur surrounding the Pacific Ocean. An instrument is used to measure the power or intensity of the earthquake called a seismometer.

CSS Solved Everyday Science (GSA) Past Paper 1985

Question – 11:

Make five matching pairs from lists A and B.

List A: Sleeping sickness, Ringworm, Sulphur, Protein, Kidney, Steel, Pancreas
List B: Malpighian Tubules, Bessemer process, Amino Acids, Tsetse fly, Insulin, Contact Process, Fungus


List AList B
Sleeping sicknessTsetse fly
Ring wormFungus
SulphurContact Process
ProteinAmino Acids
KidneyMalpigian Tubules
SteelBessemer process
Miss Ambar Fiaz
CSS Solved Everyday Science (GSA) Past Paper 1986


Define: Chronometer, Lactometer, Gyroscope, Periscope, and Barometer.



It is a device used to measure the longitude at sea, a fixed location. It is a portable timepiece, which is precise enough to be used. It was discovered by John Harrison, an English horologist. It was a great invention of the time that makes long-distance sea travel much easier for the people. According to the device, one hour of time difference corresponds to 15° of longitude (360°/24 hours = 15°/hour). It is how one can measure the longitude by setting the time on the clock accordingly.

Source Google

It is a device used to measure the amount of water in the milk. “Specific gravity of milk” is the principle on which it works. It identifies how pure or impure the milk is. It is made up of a test tube and meter bulb as shown in the figure.

Source Google

It is a device used for measuring and maintaining orientation and angular velocity in satellites and space vehicles. It is widely used in compasses, ships, and steering mechanism of torpedoes, etc. It is also used in the internal guidance system of space launch vehicles, ballistic missiles, and orbiting satellites, etc.

Source Google

It is an optical device used to seeing the objects, which are out of the direct line of the sight. It works on the principle of “reflection of light” as two plane mirrors are used in it, which are parallel to each other. It consists of a system of prisms, long tube, and lenses. When light from a distant object strikes the lens, it reflects back to the periscope tube at the angle of 90 degrees. Then, the image is formed on the mirror present at the end of the tube. Usually, it is used in a submarine to identify the events happening behind the wall. This is how it works.

Source Google

It is a device used to measure atmospheric pressure. As air possesses weight by which atmospheric pressure varies with the change in distance, above or below the sea level, so it can be measured with the barometer. It is also used to measuring altitude. It is of two types.

  1. Mercury barometer
  2. Aneroid barometer
Source Google
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Question – 13:

Where do the following animals occur?

Kiwi, Kangaroo, Ostrich, Rhea, Rattle snake, Snow leopard, and Yak.


KiwiNew Zealand
RheaSouth America
Rattle snakeAmerica
Snow leopardCentral Asian mountains
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Question – 14:

Distinguish between the following:

  1. Optical telescope and radio telescope
  2. Weather and climate
  3. Isotherm and isobar
  4. Smallpox and measles
  5. Erosion and corrosion
  6. Epidemic and endemic
  7. Cast iron and wrought iron


Optical telescope and radio telescope

Optical telescope and radio telescope

Optical TelescopeRadio Telescope
To focus visible light coming through the aperture, polished mirrors or lenses are used in optical telescope.Contrary to the optical telescope, it is used to observe much longer wavelength than visible light. It uses a dish to focus the radio waves.
Miss Ambar Fiaz
Weather and climate
Weather indicates the daily atmospheric pressure of particular place at a particular day. It varies from place to place.It is comprised of climatic elements; such as humidity, rainfall, sunshine, moisture, temperature, winds, and precipitation of a particular place for a long time.
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Isotherm and isobar
On weather maps, it is a line drawn, which indicates the atmospheric temperature. It indicates the change in temperature and helps in describing weather pattern on large scale across a region on the map. On weather maps, it is a line drawn, which indicates the atmospheric pressure. It indicates the change in pressure and helps in describing weather pattern on large scale across a region on the map.     
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Small pox and measles
In small pox disease, rashes on the body appear two to four days after the fever. It invades into the skin.In measles disease, fever and rashes appear at the same time. It does not protrude into or out of the skin.
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Erosion and corrosion
It is a geological process by which materials present on the earth are transported from one place to another with the help of natural forces; such as, water or wind.It is a chemical reaction, which progressively weakens metal and destroys it ultimately. It happens due to the chemical reaction of metals to the environment. 
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Epidemic and endemic
When a disease attacks many people at same time and may spread through communities is called epidemic. If it attacks globally, it is called pandemic. For example, cholera.When a disease exists in a specific community or a country permanently is called endemic. As malaria-endemic remains in Africa.
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Cost iron and wrought iron
Cast ironWrought iron
It is comprises of iron-carbon alloys in which carbon content is more than 2%. It is widely used in the kitchen utensils used for pan-frying, roasting, baking, and broiling, etc.In wrought iron, the amount of carbon used is lesser than in cast iron. It is stronger than cast iron. It is used to making metal gates, iron railings, and decorative items, etc.
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Question – 15:

Define any five of the following:
Heavy water
Food Chain


Heavy water:

In heavy water, deuterium is present instead of the common hydrogen-1 isotope, which is used to making hydrogen in common water. One molecule of heavy water is consists of two deuterium atom and one oxygen atom. The weight of heavy water is not greater than normal water because in water molecule oxygen is responsible for 89% of the weight. When it is in its pure form, its density is 11% greater than common water.

Chemical formula:

The chemical formula of heavy water is D2O.

Chemical composition:

Its chemical composition is:

Source Google

Is heavy water potable?

Since it has different chemical properties than common water, it is not potable. If one drinks more than 20 gallons of heavy water, one would die. Thus, heavy water is not potable.

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Food Chain:

In a food chain, the matter and energy is transferred from one organism to another in the form of food. It shows how organisms are related to each other by the food they eat. It shows the connection between many plants and animals in terms of food dependence. A diagram representing the flow of food energy from one organism to another is displayed hereunder.


Source Google

This is how food energy is transferred from producer (grass) to decomposer (fungi). Food chains combine to form food web.


It is a type of relationship between two organisms benefitting each other or at least one of the organisms is called Symbiosis. It is a cooperative relationship such as mutualism between two persons or groups.

There are three basic types of symbiosis.

  • Mutualism
  • Commensalism
  • Parasitism


The relationship between anemone and clownfish is an example of symbiosis. The anemone provides shelter to the clownfish and takes nutrients in return. It is a common example of symbiosis, mutualism.


When plants show growth in response to gravity is known as geotropism. Geotropism of plants is of two types.

  • Positive geotropism:

When plant shows growth towards the soil, is called positive geotropism.

  • Negative geotropism:

When the stem of the plant shows upward growth, is called negative geotropism as shown in the figure.

Source Google

In the human body, when the endothelium has damaged because of smoking, high level of glucose, high blood pressure, fat, and cholesterol in the blood, it causes arteriosclerosis. It makes the blood vessels, which carries oxygen and nutrients from the heart to rest of the body, thick that restricts the blood flow towards the organs. It is a curable disease, which can be cured by taking healthy diet, exercising, and medication if needed. A damaged artery because of arteriosclerosis is shown below.

Source Google

When a body lacks sufficient amount of blood-clotting proteins, blood does not clot normally anymore, which is a disorder in the human body called haemophilia. Having this disorder, it may cause a person to bleed longer after an injury as compared to a normal person. It is rarely found in females as compared to males. It is of three types mainly:

  • Hemophilia A
  • Hemophilia B
  • Hemophilia C

The difference between rate of bleeding in a normal and affected person is shown hereunder.

Source Google

It is a disease caused by yeast on the skin or mucous membrane. It may appear in different parts of the skin and shows symptoms accordingly. The common symptoms include itching, white discharge, and rash on the skin. It is a type of infection, which leaves patches of inflammation of different shape and size on the skin. It is a curable disease and can be treated by using antifungal medicine prescribed by the doctor.

Source Google
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Miss Ambar Fiaz is an M.S Physics, and being a lecturer, she has years of experience of providing coaching on Science subjects. On the request of cssprepforum, she has agreed to solve all the CSS GSA Past Papers to let aspirants how to attempt GSA paper in the CSS exam to score the maximum. She has been providing guidance to thousands of competitive aspirants on how to attempt science papers and what to prepare.

I have decided to solve all the CSS Everyday Science (Now General Science & Ability – GSA) papers to let aspirants know how to attempt the paper to fetch up to 90 marks. GSA paper of CSS is one of the most scoring papers if an aspirant gives it a serious read. Currently, the issue that thousands of CSS aspirants face is they are just provided low-quality study materials: books & notes but are never told how to attempt the paper. MISS AMBAR SAYING

Like other competitive students, If you have a story to tell, guidance to help, knowledge to educate, or a perspective that can help CSS aspirants daily, welcome to CSSPrepForum. It is free to get your opinions, viewpoints, judgements, and thinking published, whether it is a blog, article, essay, application, letter, precis, comprehension, MCQs, or anything that helps competitive youth of Pakistan. CSSPrepForum is a place that let you connect with thousands of competitive readers, and helps your voice heard across the community. Let’s start writing and get your voice heard to those who are looking for you. Email Your Write-ups at 

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